The objectives of this study are to define the usefulness and accuracy of urine cytology in the diagnosis of bladder cancer with special respect to tumor characteristics such as: 1. Histologic type of cancer, 2. Grade, 3. Size and, 4. Stage, and to compare cytology to cystoscopy as a diagnostic tool in bladder cancer. Cytologic criteria will be defined. Cystoscopically occult cases of bladder cancer (very early, in-situ), detected by cytology will be studied closely and furnish indispensable information about the evolution of early bladder cancer in humans. This study will utilize existing large, well organized and functioning urologic and urine cytology practices which include some 230 new cases annually and 1400 patients being followed after treatment for bladder cancer. Complete data will be recorded on each patient in a precoded fashion suitable for computer analysis. Additionally, technical factors in specimen handling and preparation will be studied as well as prefixation techniques to allow for delays in shipping. BIBLIOGRAPHIC REFERENCES: Farrow, G.M, Utz, D.C. and Rife, C.C.: Early Bladder Cancer. Morphologic and clinical observations on 21 cases treated by total cystectomy. Submitted Cancer Research, Oct. 21, 1975; Farrow, G.M.: Morphology, Nomenclature and Natural History of Early Human Bladder Cancer. Presented Conference on Early Lesions and the Development of Epithelial Cancer. Oct. 21, 1975. National Institutes of Health.